A Prospective, Double-Blind, Randomized, Placebo-Controlled, Crossover Study Using an Orally Administered Oxalate Decarboxylase (OxDC).

Background: Hyperoxaluria is typically associated with excessive oxalate intake in the diet, decreased dietary calcium, hyperabsorption of oxalate, or increased endogenous production of oxalate. The disorder spectrum extends from recurrent kidney stones to ESKD. This clinical trial sought to evaluate the effectiveness of an acid stable oxalate decarboxylase (OxDC) to reduce urinary oxalate in healthy subjects on a high-oxalate diet. Methods: In this prospective, double-blind, randomized, placebo-controlled, crossover clinical trial, 33 healthy volunteers were randomized into two crossover sequences separated by a 2-day washout period. A controlled high-oxalate diet (750-800 mg oxalate, 500-550 mg calcium daily) was utilized, and six 24-hour urine collections were measured. Subjects were given approximately 1000 U (micromoles per minute per milligram) of OxDC or placebo with meals three times daily during the 4 days of treatment. Results: Urinary oxalate significantly decreased with OxDC treatment. The baseline corrected within-subject mean reduction in 24-hour urinary excretion (after OxDC dosing versus high-oxalate baseline preceding treatment) was 12.5 mg or 29% (P<0.001). OxDC treatment was effective (>5% reduction) in 31 of 33 subjects (94%). Compared with placebo, OxDC produced a 24% reduction (P<0.001) in 24-hour oxalate excretion. Other urinary parameters (creatinine, uric acid, citrate, magnesium, calcium) were not affected by OxDC. No serious adverse events and no product-related adverse events occurred. Conclusions: An orally administered OxDC is capable of significantly reducing urinary oxalate levels in healthy volunteers on a high-oxalate diet without affecting creatinine clearance, urine creatinine, or other solutes related to supersaturation of calcium oxalate. Clinical Trial registry name and registration number: Evaluation of Nephure, and the Reduction of Dietary Oxalate, in Healthy Volunteers, NCT03661216.

Prostate Cancer With Metastatic Lytic Bone Lesions: Positive Bone Scan Post Docetaxel Chemotherapy in the Setting of Clinically Successful Treatment.

Current treatment of metastatic bone prostate cancer with Docetaxel chemotherapy per CHAARTED trial is standard of care. Timing of CT and bone scintigraphy for evaluation of successful treatment of lytic lesions is not available in the literature. We present a case of a 70 year old male with PSA of 586 and wide spread metastatic bone lytic lesions, who underwent androgen deprivation therapy and six cycles of Docetaxel chemotherapy. The patient had clinically successful treatment. Contrast enhanced CT scan demonstrated sclerotic bone lesions with PSA 2.5 at this point in treatment; however, 99mTc-MDP bone scintigraphy remained positive for metastatic lesions.